Provide state change details for an the application

The current details on the web UI for an application show only the state that the application is in. It does not provide details on when the application changed to that state.
Since there is no guarantee that the application has transitioned directly from being created to a Running state or any other we should display the time stamp of the last state change.

This detail is already tracked in the core but not exposed anywhere.
This is just for exposing the value in REST and web UI